1. Field of Invention
The present invention relates to a grinding machine, and more particularly to a grinder for polishing and mirror finishing a surface of a workpiece, wherein the grinder comprises a grinding agent dispenser built-in with the grinder for lubricating and/or cooling down the surface of the workpiece during the machining process of grinding.
2. Description of Related Arts
A grinding machine is commonly and widely used in the machining process for polishing, finishing, turning, or cutting a workpiece, e.g. a piece of wood or metal, so that the original material of the workpiece is able to be processed to a desired size, shape or quality via the grinding machine.
Traditionally, lubricants or cooling fluid are conducted in the grinding machining process in order enhance the quality of workpiece, such as a roughness of the workpiece surface. Most of the grinding machines, which is able to machine a relatively higher-grade mirror finishing surface, such as lower roughness (Ra≦0.1 μm), adapt a lubrication system for lubricating the surface of workpiece and the grinder tool of the grinding machine. The liquid lubricant or cooling agent is commonly supplied to the surfaces of workpiece and the grinder tool via incorporating a mercury oil dispensing system or manually delivering the lubricant or cooling agent to the surfaces by an operator.
During the actual machining process, the rolling tool of the grinder is contacting with the workpiece to form a substantially sealed or closed structure, so that the delivering of lubricant or cooling agent is a main concerning issue. It is hard to efficiently supply the lubricant to the workpiece or rolling tool surface to lubricate and cool down the temperature, which might keep increasing due to the fraction between the grinder tool surface and the workpiece while grinding.
Take the cylindrical grinder for example. While the grinding process, the grinder is usually moving in radius direction in related to the workpiece, i.e. either the grinder or the workpiece is rotatably driven to move, so that the grinder is able to rotatably grinding or refining the surface of the workpiece to achieve the purpose of polishing or mirror finishing process. The lubricant or cooling agent applied during the process may be splashed out while the spinning of the cylindrical grinder due to the centrifugal force of the grinder or workpiece. Therefore, the lubricant or machining oil may not be able to efficiently play the role for lubricating and/or cooling.
The increasing temperature during the grinding process may cause damages to the workpiece if cannot control the temperature under a certain requirement, such as reducing the residual stress, fatigue strength, or deforming the shape of the workpiece. When the cooling of the workpiece and the grinder tool during the grinding process is not timely, the life time of both of the workpiece and the grinder tool may be gradually reduced, and the accuracy of the machining process may be decreased.
Thus, in order to prevent not timely cooling or lubricating, the operator may either repeatedly smear over the surfaces of the workpiece and the grinder, or increase the mercury oil pump power to increase the flow of lubricant or cooling agent.
However, the amount of the lubricant or cooling agent being supplied during the grinder process is gradually increased. The over supplied lubricant or cooling agent may unevenly and overly cover part of the surface of the workpiece, so that the operator is unable to observe the changes at the surface of the workpiece. It is inconvenient for the operator to control the quality of the grinding process for processing the workpiece. Meanwhile, the maintenance and cleaning of the grinder tool is another concern. The structures of most of the existing grinders are hard to reach the inner tiny details. The grinder may have to be demolished or broken down to reach the gaps for cleaning. It is not only time consuming, but also increase the manufacturing cost.